From EP 1 559 980 a generic oil cooler comprising at least two heat exchanger plates stacked one over the other in stacking direction, and a cover plate, is known, wherein a fluid channel extends between the cover plate and the adjacent heat exchanger plate. Furthermore, a thermostatic valve is provided, which is connected to the fluid channel of the cover plate in a fluid-transmitting manner by means of its thermostatic valve housing.
From DE 10 2008 020 609 A1 a further oil cooler is known, comprising cooling channels, arranged in a housing, and a bypass which is able to be closed by a bypass valve. The valve body of the bypass valve is directed through an opening in the housing and projects in transverse direction into the bypass channel. Hereby, a variably usable oil cooler is to be able to be created.
From DE 10 2005 048 294 A1 a further oil cooler is known, comprising stacked heat exchanger plates with at least two openings, whereby the two openings form two corresponding channels and wherein flow channels are formed, in intervals between the heat exchanger plates preferably standing perpendicularly to the channels, which flow channels are connected hydraulically to the channels. Furthermore, a valve element is provided, which opens or respectively closes one of the channels in order to direct medium, for example oil, flowing there, either through the flow channels or through a bypass channel.
Generally, in oil coolers known hitherto from the prior art, it is known to manufacture a thermostatic valve separately and to install this onto a finished soldered heat exchanger block. For this, of course a sealed connection must be created between the heat exchanger block and the thermostatic valve, which must be monitored and verified by means of laborious leakage tests, in this case even double leakage tests. Here, firstly the heat exchanger block is subjected to a leakage test and subsequently the structural unit of heat exchanger block and thermostatic valve housing are subjected to a further leakage test.